Method for applying a container closure

ABSTRACT

A container closure having a top end wall and a depending peripheral skirt which includes an outwardly projecting land with sealing material disposed on its under surface is positioned on a container entrance mouth which has inclined closure retaining means thereon and an outwardly projecting bead below the retaining means, the closure skirt is deformed against the inclined closure retaining means on the container mouth, substantially downward pressure is applied against the closure skirt overlying the container bead to press the sealing material in the closure skirt against the container bead, and a lower edge of the closure skirt is turned under the container bead to maintain pressure between the sealing liner and the container bead.

[11 3,842,574 1 Oct. 22, 1974 1 1 METHOD FOR APPLYING A CONTAINERCLOSURE [75] Inventor: John J. Dickey, Richmond, 1nd.

{731 Assignee: Aluminum Company of America, Pittsburgh, Pa.

[22] Filed: July 18, 1973 [21] Appl. No.: 380,207

Related US. Application Data [62] Division of Ser. No. 212.235, Dec. 27,1971, Pat. No.

3,479,790 11/1969 Barge 53/42 3,645,062 2/1972 Hannon ..53/42 PrimaryExaminerRichard J. Herbst Attorney, Agent, or FirmDavid W. Brownlee l 57 1 ABSTRACT A container closure having a top end wall and a dependingperipheral skirt which includes an outwardly projecting land withsealing material disposed on its under surface is positioned on acontainer entrance mouth which has inclined closure retaining meansthereon and an outwardly projecting bead below the retaining means, theclosure skirt is deformed against the inclined closure retaining meanson the container mouth, substantially downward pressure is appliedagainst the closure skirt overlying the container bead to press thesealing material in the closure skirt against the container bead, and alower edge of the closure skirt is turned under the container bead tomaintain pressure between the sealing liner and the container head.

3 Claims, 5 Drawing Figures METHOD FOR APPLYING A CONTAINER CLOSURE Thisis a division of application Ser. No. 212,235, tiled Dec. 27, I971,which has now issued as U.S. Pat. No. 3,771,683 on Nov. l3, 1973.

BACKGROUND OF THE INVENTION In closing a container with a closure orcap, it is conventional to provide a gasket or seal which seals thecontainer against escape of the container contents and against entry ofcontaminants. This seal may be provided in a number of locations, withthe usual seal being provided near the mouth opening of the containerand with retaining means on the container and closure outwardly of theseal. Other combinations have provided a seal below the retaining meansso that contaminants cannot collect in the closure around the retainingmeans in the combination. It is also known as disclosed in US. Pat. Nos.3,286,868 and 3,286,867 to provide two sealing gaskets, one of whichseals the closure against the container adjacent the container mouthopening and the other of which seals the closure against the containeroutwardly of the closure retaining means. As described in those patents,the dual sealing means prevents insect infestation into the area of theretaining means and also prevents the contents of the container fromcollecting on the retaining means.

Although the closure container combinations described in U.S. Pat. Nos.3,286,868 and 3,286,867 have been useful in preventing infestation intothe area of the retaining means, the outer seal in this combination maynot prevent water or other gaseous or liquid contaminants from reachingthe area of the retaining means when the exterior of the sealedcontainer is exposed to a relatively high pressure as happens when sucha combination is subjected to autoclaving by high pressure steam or thelike. Accordingly, an improved closure-container combination is desiredwhich will provide a high pressure seal on both sides of the closureretaining means to substantially preclude contamination of the contentsof the container and the retaining means.

SUMMARY OF THE INVENTION This invention provides a closure which has atop end wall and a depending peripheral skirt therearound with sealingmaterial on the inner surface of the skirt near its bottom edge andwhich is applied to a container entrance mouth having inclined closureretaining means thereon and an outwardly projecting bead below theretaining means by deforming the closure skirt against the closureretaining means, applying substantially downward pressure against theclosure skirt overlying the container head to press the sealing materialagainst such container bead, and turning a lower edge of the closureskirt under the container bead to maintain pressure between the sealingmaterial and the container bead.

Accordingly, an object of the invention is to provide a containerclosure which can be applied to a container entrance mouth with highpressure hermetic seals on both sides of the closure retaining means.

Another object of the invention is to provide a closure having adepending peripheral skirt with a ring of sealing material on its innersurface which is pressed against a bead on a container mouth belowclosure retaining means thereon to provide a hermetic seal outwardly ofthe closure retaining means on the container.

Another object of the invention is to provide a method of applying aclosure to a container by deforming the closure skirt against retainingmeans on the container mouth and pressing a ring of sealing materialaround the inner surface of the closure skirt against a container beadbelow the closure retaining means and turning a lower edge of theclosure skirt under the container bead.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects andadvantages of the invention will be more fully understood andappreciated with reference to the following description and the drawingsattached thereto:

FIG. 1 is a cross sectional view of a preferred embodiment of a closureof the invention on a container entrance mouth prior to sealing;

FIG. 2 is a cross sectional view similar to FIG. 1 illustratingdeforming of the closure skirt against closure retaining means on thecontainer entrance mouth;

FIG. 3 is a cross sectional view similar to FIGS. 1 and 2 illustratingthe application of top pressure against a shoulder on the closure skirtto press sealing material in the skirt against a bead on the containerentrance mouth;

FIG. 4 is a cross sectional view similar to FIGS. 1-3 illustratingturning of a lower edge of the closure skirt under the bead on thecontainer entrance mouth; and

FIG. 5 is a cross sectional view similar to FIGS. 1-4 illustrating asealed closure container combination.

DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION A preferredembodiment of the invention is illustrated and described as comprisingas a roll-on pilferproof closure which is particularly adapted forsealing a container for intravenous solutions for hospital use.

Referring more particularly to FIGS. l-5, FIG. 1 illustrates a closure10 formed from sheet metal or other permanently deformable material, andpreferably from sheet aluminum, which is loosely positioned over anentrance mouth 12 of a container 14. Container 14 is preferablycomprised of glass although other permanently moldable materials knownto the container industry such as plastic and metal may be utilized.Container 14 has an entrance mouth 12 with inclined retaining means 16thereon, which are threads in the preferred embodiment although othercommonly known retaining means may be used. A circumferential bead 18 isdisposed below the retaining means 16 and preferably extends outwardlyfrom the container main body beyond the inclined retaining means 16although this is not considered to be critical of the invention. Bead 18is essentially rectangular in cross section having a relatively smallradius R on its top outward corner and another radius R on its bottomoutward corner. Radius R on bead 18 is approximately 5 /64 in. in thepreferred embodiment which is selected for illustration, however theinvention is not limited thereto. Radius R is relatively small to permiteffective sealing of closure 10 to container 14 at this location as willhereinafter be discussed. Radius R functions to accept a pilferproofband 20 at the bottom of closure and the dimensions of radius R are notcritical and may vary as is obvious to one skilled in the art.

Closure 10 is comprised of a top end wall 22 and a depending peripheralskirt 26 and may have a knurled band 24 formed therein on the cornerbetween said top end wall and skirt to facilitate gripping of theclosure to remove or reapply it. Said depending skirt 26 extendsdownwardly from top end wall 22 and may have an inwardly directedcircumferential rib 27 formed therein adjacent top end wall 22, said rib27 functioning to retain a sealing composite liner 28 againstundersurface 30 of the top end wall.

Sealing liner 28 which has been selected for illustration comprises acomposite of materials which are particularly adapted for sealingintravenous solution. It will be apparent, however, that other sealingmeans known in the art may also be used in a closure of the inventionfor sealing containers. Composite sealing liner 28 may comprise a bottomlayer of gilsonite 32, an intermediate layer of rubber 34, a flangedmetal disc 36, and a top layer of high density polyethylene syntheticfiber 38 such as marlex facing top end wall 22 of the closure. Metaldisc 36 is especially designed to restrain rubber layer 34 around itsperiphery so that the rubber cannot extrude outwardly when top sealingpressure is applied against closure 10. Variations in the composition,application and arrangement of the sealing liner may be made such ascoating inner surface 30 of the top end wall with a uniform sealingmaterial or providing a disc of polyvinyl chloride or other likematerial thereagainst as is commonly known in the container industry.

Depending peripheral skirt 26 of closure 10 includes a substantiallyvertical top portion to be deformed against closure retaining means on acontainer mouth, an outwardly extending shoulder or sealing land 40 anda lower band portion 20 projecting downwardly from the outer edge of thesealing land. As illustrated, a rounded corner 58 may be provided inclosure skirt 26 between its upper portion and sealing land 40, and asecond rounded corner 60 may be provided between the sealing land andband 20. The dimensions of such radii 58 and 60 are not being consideredmaterial to the invention.

It is a feature of this invention that sealing material 44 is providedon the inner surface of closure skirt 26 around its entire circumferencein corner 60 between sealing land 40 and lower portion 20 of the skirtso that it will contact top radius R, of container bead 18 when closure10 is secured to container 14 as hereinafter described. An example ofsuch sealing material 44 is plastisol which may be coated onto the innersurface of closure skirt 26 in corner 60 of sealing land 40. Flowableplastisol may be deposited in the corner 60 of sealing land 40 with amachine conventionally used in the closure-container industry and thecoated closure may then be heated to cure the plastisol in place. Ascured, the plastisol will preferably be adhered to closure skirt 26 sothat compressible liner 44 will not fall out of do sure 10 duringhandling. Plastisol is used by way of example, it being apparent thatother materials may also be disposed in the skirt 26 such as for examplerubber O-rings or polyvinex chloride gaskets, among others.

Band portion 20 of skirt 26 extends downwardly from the corner 60 ofsealing land 40 and is adapted to have at least a bottom edge thereofformed under outwardly projecting bead 18 on container 14, and may havea line of weakening 46 such as a line of slits and bridges locatedcircumferentially therearound separating a locking band on the bottom ofthe closure from the remainder of the closure. The bridges in theclosure skirt are designed to rupture upon closure removal to leave thelocking band on container 14. Such a locking band is commonly referredto as a pilferproof band since it provides evidence that acontainer-closure combination has been opened or pilfered.

The aforementioned description of a closure with a locking orpilferproof band thereon is a preferred embodiment of the invention, itbeing recognized that there are other means of making a closurepilferproof. For example, a closure of the invention may have a line ofslits and bridges therearound separating a locking band on the bottom ofthe closure from the reaminder of the closure, and also may have aplurality of vertical lines of weakening such as scores in the lockingband which rupture on removal of the closure from a container to dividethe band into segments between the ruptured vertical lines. On removalof such a closure from a container, the segments may bend on the line ofbridges and be flared outwardly by the camming action of the lockingshoulder of the container. The segments remain attached to the closureskirt and are removed with the closure. A closure of the invention mayalso have only a plurality of vertical score lines in the lower portionof the closure skirt which is adapted to be turned under a lockingshoulder on a container to form a locking effect therewith, and includesno circumferential line of slits and bridges. When such a closure isremoved from a container, the vertical score lines rupture to divide thebottom portion of the closure skirt into segments between the rupturedscores. These segments may be flared outwardly by the camming action ofthe locking shoulder on a container to permit removal of the closurewith the segments attached thereto.

FIG. 2 illustrates closure 10 in the first step of securing the closureto container entrance mouth 12. Closure 10 is positioned over containerentrance mouth 12 and downward pressure of approximately 200-700 pounds,and preferably about 300 pounds, is applied to closure 10 with pressureblock 50 or the like attached to a standard capping machine (not shown).The top portion of depending peripheral skirt 26 is then deformedagainst inclined closure retaining means 16 on container 14 by means ofrollers 52 while the top pressure is maintained on closure 10 withpressure block 50. To effect this deformation, rollers 52 are movedagainst and around closure skirt 26 to reform it permanently againstcontainer retaining means 16 and thereby form threads in closure skirt26. The top pressure initially seals closure 10 at container entrancemouth 12 and deformation of closure skirt 26 against inclined retainingmeans 16 holds closure 10 on container 14 in addition to holding topsealing liner 28 against closure 10 and container entrance mouth 12thereby providing container14 with a high integrity top seal.Alternatively, it is also believed to be possible to secure a closurehaving threads embossed therein on a container by turning such a closureonto the container without the application of any external pressureother than the closure itself as it turns onto container.

According to the present invention, a second capping machine (not shown)next seals closure 10 against container 14 to provide a lower sealoutwardly of the closure retaining means as illustrated in FIG. 3.Downward pressure is applied against sealing land 40 with a collar orbushing 54 which preferably has a tapered throat therein to direct asubstantially downward pressure against the land 40 and the roundercorner R of container bead 18. Application of the substantially downwardpressure against closure at sealing land 40 compresses sealing liner 44against the relatively small top radius R of container bead 18 to form aseal therebetween. Pressures of approximately 300 pounds have been foundto work well for such purposes, although it is believed that pressuresin the range of 100500 pounds may be used.

FIG. 4 illustrates the final step of securing closure to container 14wherein a bottom portion of band is tucked under container bead 18 witha forming tool 56 while collar 54 maintains substantially downward pressure against sealing land of closure 10. After band 20 has been tuckedunder bead 18 at radius R the pressure of collar 54 against land 40 isreleased, and the inwardly turned edge of closure 10 against containerbead 18 holds the bottom portion of the closure in a restrainedcondition with sealing material-compressed against an upper surface ofcontainer bead 18.

From the above description, it should now be apparent that the presentinvention provides a tight compression seal at the interface of closuresealing land 40 and container bead 18 as shown in FIG. 5. Sealingmaterial 44 is maintained in compression by the downward restraintprovided by the bottom portion of band 20 once this portion is tuckedunder container bead 18 at corner R Though some previously knownclosures are sealed against containers at this relative location today,the prior art closures have relied upon sealing pressures produced by aninterference fit of the seal against the container and have not beensealed with the assistance of an external force which compresses theseal against the container and such compressed seal thereafter beingmaintained by the rolled edge of pilferproof band on the closure. Thepreviously known seals therefore could have their integrity violatedwhen the container and its attendant contents are exposed to relativelyhigh internal or external pressures such as are produced duringautoclaving of a sealed container. With the present invention, however,high pressures developed during sterilization in autoclave apparatuswill not violate the seal outwardly of the closure retaining means sincethis sea] is maintained under compression by the rolled edge of theclosure under the container head. The lower seal in the presentinvention is substantially impervious to all contaminants, be theysolid, liquid or gaseous, both at room temperature and pressure andelevated temperatures and'pressure normally used to sterilize medicalsupplied in an autoclave because the lower seal is positively compressedagainst and partially around the container bead relatively small radius.This is a substantial improvement over prior closures which did notinclude compression of a seal outwardly of the closure retaining means.

Removal of closure 10 from container 14 may be effected by turningclosure 10 relative to container 14. Since the lower edge of pilferproofband 20 is turned under container bead 18 and the band has no verticalweakening in the closure selected for illustration, the band cannot beremoved from the container. Instead, pilferproof band 20 separates fromthe remainder of closure 10 at the parting line around its circumferenceformed by breaking of bridges 48. Pilferproof band 20 remains oncontainer 14 after closure 10 is completely removed. However, in some ofthe previously described alternative forms of a closure of the inventionwhich include vertical scores in the locking band portion of theclosure, the vertical scores are intended to be ruptured upon removal ofthe closure to divide the band into segments which are removed with theclosure.

Closure 10 may be re-secured to container 14 by screwing it ontocontainer 14. When closure 10 is resecured on container 14, a seal ismade both at the container entrance mouth 12 and container bead 18,although the seal at container bead 18 is not held under compression asit was prior to initial opening. This is not important, however, sincethe container-closure combination will not normally be subjected toautoclaving or high pressure differentials subsequent to initial openingthereof. Pilferproof band 20 is separate from closure 10 such thatvisual inspection of package will reveal that the closure-containercombination has been previously opened.

It is therefore seen that an improved closure and a method of applyingthe same to a container have been illustrated and described in which aseal is provided outwardly of the container retaining means on thecontainer to prevent ingress of contaminants into the space betweenclosure skirt and container finish. By preventing contaminants fromentering this area, the closure retaining means on the container ismaintained in a sterile condition and will not contaminate thecontainers contents when emptied from the container.

Whereas a preferred embodiment of the invention has been illustrated anddescribed, it will be apparent to those skilled in the art that numerousvariations can be made therein without departing from the scope of theappended claims.

What is claimed is:

l. A method of sealing a closure on a container comprising in sequencethe steps of providing a container having an entrance mouth with closureretaining means thereon and an outwardly projecting circumferential beadbelow said retaining means, positioning a closure on the entrance mouth,said closure having a top end wall, a depending peripheral skirtextending therefrom including an upper portion, a land directedoutwardly from the bottom of the upper portion and a band depending froman outer edge of the land, said closure further having a sealingmaterial disposed therein overlying the upper surface of said containerbead,

forming said closure skirt against said retaining means on the containermouth,

applying substantially downward pressure against said closure skirtoverlying the container bead to press the sealing material against thecontainer bead, and

turning at least a portion of the band on the closure skirt under saidcontainer bead to hold the sealing material in the closure skirt pressedagainst the container bead.

2. A method of sealing a closure on a container according to claim 1wherein 7 8 said closure is provided with sealing material therein upperseal between the container and closure.

adjacent the container entrance mouth above the 3. A method of sealing aclosure on a container acclosure retaining means and cording to claim 1wherein a pressure in the range of substantially downward pressure isapplied against 300-500 pounds is applied against the closure land saidtop end wall prior to, and during, deformation overlying the containerbead to press the sealing mateof said closure depending skirt againstsaid retainrial thereagainst.

ing means on the container mouth to provide an

1. A method of sealing a closure on a container comprising in sequencethe steps of providing a container having an entrance mouth with closureretaining means thereon and an outwardly projecting circumferential beadbelow said retaining means, positioning a closure on the entrance mouth,said closure having a top end wall, a depending peripheral skirtextending therefrom including an upper portion, a land directedoutwardly from the bottom of the upper portion and a band depending froman outer edge of the land, said closure further having a sealingmaterial disposed therein overlying the upper surface of said containerbead, forming said closure skirt against said retaining means on thecontainer mouth, applying substantially downward pressure against saidclosure skirt overlying the container bead to press the sealing materialagainst the container bead, and turning at least a portion of the bandon the closure skirt under said container bead to hold the sealingmaterial in the closure skirt pressed against the container bead.
 2. Amethod of sealing a closure on a container according to claim 1 whereinsaid closure is provided with sealing material therein adjacent thecontainer entrance mouth above the closure retaining means andsubstantially downward pressure is applied against said top end wallprior to, and during, deformation of said closure depending skirtagainst said retaining means on the container mouth to provide an upperseal between the container and closure.
 3. A method of sealing a closureon a container according to claim 1 wherein a pressure in the range of300-500 pounds is applied against the closure land overlying thecontainer bead to press the sealing material thereagainst.